static Boolean attempt_three_to_two(
Triangulation *manifold)
{
EdgeClass *edge,
*where_to_resume;
/*
* Note: It's easy to prove that if the three original Tetrahedra
* are positively oriented, then the two new Tetrahedra must be
* positively oriented as well. So we needn't worry about negatively
* oriented Tetrahedra here.
*/
for (edge = manifold->edge_list_begin.next;
edge != &manifold->edge_list_end;
edge = edge->next)
if (edge->order == 3)
if (concave_edge(edge) == TRUE)
{
if (three_to_two(edge, &where_to_resume, &manifold->num_tetrahedra) == func_OK)
return TRUE;
else
/*
* The only reason three_to_two() can fail is that the
* three Tetrahedra surrounding the EdgeClass are not
* distinct. But by Corolloary 3 of "Convex hulls..."
* this cannot happen where the hull is concave.
*/
uFatalError("attempt_three_to_two", "canonize_part_1");
}
return FALSE;
}
void cube_to_rects()
{
if (m_sighted)
{
m_quads[0][0].position = three_to_two(m_abs_posits[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]]);
m_quads[0][1].position = three_to_two(m_abs_posits[!m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]]);
m_quads[0][2].position = three_to_two(m_abs_posits[!m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]]);
m_quads[0][3].position = three_to_two(m_abs_posits[m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]]);
m_quads[0][0].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_quads[0][1].color = square_to_color(m_color, m_abs_squares[!m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_quads[0][2].color = square_to_color(m_color, m_abs_squares[!m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_quads[0][3].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_average_squares[0] = 0.25f*(m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]] +
m_abs_squares[!m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]] +
m_abs_squares[!m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]] +
m_abs_squares[m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]]);
m_quads[1][0].position = three_to_two(m_abs_posits[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]]);
m_quads[1][1].position = three_to_two(m_abs_posits[m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]]);
m_quads[1][2].position = three_to_two(m_abs_posits[m_cubordinates[0]][!m_cubordinates[1]][!m_cubordinates[2]]);
m_quads[1][3].position = three_to_two(m_abs_posits[m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]]);
m_quads[1][0].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_quads[1][1].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_quads[1][2].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][!m_cubordinates[1]][!m_cubordinates[2]], m_sight_inverse);
m_quads[1][3].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]], m_sight_inverse);
m_average_squares[1] = 0.25f*(m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]] +
m_abs_squares[m_cubordinates[0]][!m_cubordinates[1]][m_cubordinates[2]] +
m_abs_squares[m_cubordinates[0]][!m_cubordinates[1]][!m_cubordinates[2]] +
m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]]);
m_quads[2][0].position = three_to_two(m_abs_posits[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]]);
m_quads[2][1].position = three_to_two(m_abs_posits[m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]]);
m_quads[2][2].position = three_to_two(m_abs_posits[!m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]]);
m_quads[2][3].position = three_to_two(m_abs_posits[!m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]]);
m_quads[2][0].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_quads[2][1].color = square_to_color(m_color, m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]], m_sight_inverse);
m_quads[2][2].color = square_to_color(m_color, m_abs_squares[!m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]], m_sight_inverse);
m_quads[2][3].color = square_to_color(m_color, m_abs_squares[!m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]], m_sight_inverse);
m_average_squares[2] = 0.25f*(m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]] +
m_abs_squares[m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]] +
m_abs_squares[!m_cubordinates[0]][m_cubordinates[1]][!m_cubordinates[2]] +
m_abs_squares[!m_cubordinates[0]][m_cubordinates[1]][m_cubordinates[2]]);
}
}